registry/layer.go
Stephen J Day e158e3cd65 Initial implementation of Layer API
The http API has its first set of endpoints to implement the core aspects of
fetching and uploading layers. Uploads can be started and completed in a single
chunk and the content can be fetched via tarsum. Most proposed error conditions
should be represented but edge cases likely remain.

In this version, note that the layers are still called layers, even though the
routes are pointing to blobs. This will change with backend refactoring over
the next few weeks.

The unit tests are a bit of a shamble but these need to be carefully written
along with the core specification process. As the the client-server interaction
solidifies, we can port this into a verification suite for registry providers.
2014-11-21 19:12:20 -08:00

79 lines
1.8 KiB
Go

package registry
import (
"net/http"
"github.com/docker/docker-registry/digest"
"github.com/docker/docker-registry/storage"
"github.com/gorilla/handlers"
"github.com/gorilla/mux"
)
// layerDispatcher uses the request context to build a layerHandler.
func layerDispatcher(ctx *Context, r *http.Request) http.Handler {
dgst, err := digest.ParseDigest(ctx.vars["digest"])
if err != nil {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
ctx.Errors.Push(ErrorCodeInvalidDigest, err)
})
}
layerHandler := &layerHandler{
Context: ctx,
Digest: dgst,
}
layerHandler.log = layerHandler.log.WithField("digest", dgst)
return handlers.MethodHandler{
"GET": http.HandlerFunc(layerHandler.GetLayer),
"HEAD": http.HandlerFunc(layerHandler.GetLayer),
}
}
// layerHandler serves http layer requests.
type layerHandler struct {
*Context
Digest digest.Digest
}
// GetLayer fetches the binary data from backend storage returns it in the
// response.
func (lh *layerHandler) GetLayer(w http.ResponseWriter, r *http.Request) {
layers := lh.services.Layers()
layer, err := layers.Fetch(lh.Name, lh.Digest)
if err != nil {
switch err {
case storage.ErrLayerUnknown:
w.WriteHeader(http.StatusNotFound)
lh.Errors.Push(ErrorCodeUnknownLayer,
map[string]interface{}{
"unknown": FSLayer{BlobSum: lh.Digest},
})
return
default:
lh.Errors.Push(ErrorCodeUnknown, err)
return
}
}
defer layer.Close()
http.ServeContent(w, r, layer.Digest().String(), layer.CreatedAt(), layer)
}
func buildLayerURL(router *mux.Router, r *http.Request, layer storage.Layer) (string, error) {
route := clonedRoute(router, routeNameBlob)
layerURL, err := route.Schemes(r.URL.Scheme).Host(r.Host).
URL("name", layer.Name(),
"digest", layer.Digest().String())
if err != nil {
return "", err
}
return layerURL.String(), nil
}